All industrial, construction, and consumer products strive to identify raw materials from renewable resources grown or otherwise harvested from the plant or animal kingdom. The expense and increasing scarcity of petrochemically originating raw materials only accentuate the difficulties of recycling after useful life of products made from such raw materials.
The polymer industry, which had started in the early 20th Century with renewable resources such as natural latex for rubber goods, is now returning to such renewable raw materials whenever possible.
One body of research aims at bio-derived plasticizers. An example is U.S. Pat. No. 6,797,753 (Benecke et al.), incorporated by reference herein, which discloses plasticizers derived from vegetable oils. Another is U.S. Pat. No. 7,196,124 (Parker et al.) which discloses making elastomeric materials from castor oil and epoxidized soybean oil.